Recent years have seen active development of see-through display technology and a gradual increase in products with see-through displays being put on the market. See-through displays are generally categorized into two types: “box type” referring to a liquid crystal display device with a box-like backlighting portion; and “stand-alone type” eliminating the need for the box of the backlighting portion. Of these, the box type is relatively easy to be produced but has a problem where the visible range of transparent display is limited to the bounds of the box. On the other hand, the stand-alone type allows everything in the background to be seen.
Patent Document 1 discloses a see-through display of a stand-alone type. This see-through display allows most of the light emitted by a light guiding plate to pass to the back side and illuminate the background, thereby ensuring high transparency. Moreover, light reflected toward the front side by an object in the background illuminates a liquid crystal panel as backlight, thereby displaying an image on the liquid crystal panel. In this manner, the see-through display described in Patent Document 1 realizes high transparency and also insure the clarity of a displayed image.